1. Field of the Invention
The present invention relates to an electrical connector assembly consisting of a pair of connectors to be plugged into each other and electrical connectors for it.
2. Description of the Related Art
Some of the electrical connector assemblies of this type have a plurality of pairs of contact elements to be connected. When the contact element pairs of both connectors are brought into contact with each other under contact pressures in the same direction perpendicular to the plugging direction of the connectors, the combined forces of the contact pressures are applied on the housing walls. Consequently, when the wall thickness of the housings is reduced by miniaturization of the connectors, the housing walls are deformed to move the contact elements from the regular positions, resulting in the unstable and uneven contact pressures.
In order to avoid such a problem, it has been proposed to arrange a plurality of contact elements in a zigzag fashion for alternating the contact pressures between the contact elements. An example is disclosed in Japanese patent application Kokai No. 58-126685.
As shown in FIGS. 4(A)-(C), a plurality of insertion ports 52 are provided in an elongated housing 51 along the longitudinal direction of the housing for receiving contact pins 61 of a mating connector. A retention slot 53 communicates with each of the insertion ports 52. As best shown in FIG. 4(B), the insertion ports 52 are positioned at the center of the thickness or height of the housing 51 while the retention slots 53 are provided at alternating upper and lower positions of the insertion ports 52.
In FIG. 4(C), a contact element 55 to be supported by the retention slot 53 has a base section 56 having flat faces and a resilient contact section 57 which is bent obliquely. The base section 56 is inserted in the retention slot 53 such that the contact section 57 is placed in the insertion port 52. When the contact pin 61 is put into the insertion slot 52, it makes contact with the contact section 57. In this way, all the contact pins 61 make contact with the upper and lower contact sections 57 alternately.
Consequently, the housing 51 receives upward and downward contact pressures by the contact elements 55 provided above and below the insertion ports 52, respectively. If the housing walls are satisfactorily rigid and the upper and lower contact elements are substantially equal in number, then the above contact pressures are offset.
However, the above connectors are bulky and has the following disadvantages. Since the contact elements are arranged in the zigzag fashion, the housing wall on the side where there is no contact element is thick, resulting in the large or thick connector. In addition, the contact elements extend in the longitudinal direction of the housing, resulting in the large or wide housing.
Accordingly, it is an object of the invention to provide a thin and narrow electrical connector assembly which receives a reduced load of contact pressures and an electrical connector for the assembly.
According to the invention there is provided an electrical connector assembly consisting of a pair of first and second electrical connectors, each comprising a plurality of first contact elements having first contact sections brought into contact with second contact sections of second contact elements for the other electrical connector under contact pressures in a first direction perpendicular to a plugging direction of the electrical connectors, the first and second contact elements being arranged at intervals in a second direction perpendicular to the first direction, at least one of the first and second contact sections being flexible in the first direction.
According to the invention, the first and second contact sections are situated in the same range in the first direction, and substantially equal numbers of first and second contact sections are oriented opposite in the first direction. The contact pressures upon the contact sections are canceled out so that little load is applied to the housing. The contact sections are situated in the same range in the first direction so that the thickness of housing walls can be minimized. The first and second contact elements are oriented alternately opposite in the first direction.
The contact elements are made of a metal sheet and have flat surfaces which extend in the first direction so that the contact sections have a large area in the first direction, resulting in the high strength of the contact elements and the thin walls of the housing between adjacent contact elements, making it possible to reduce the thickness of upper and lower walls of the housing. Each contact element comprises a base section which extends from each the contact section and does not exceed a maximum height of the contact element in the first direction, the base section having a projection for engagement with a housing of the electrical connector, resulting in the compact connector in the first direction. The first contact sections may be flexible, and the second contact sections of the second connector are not flexed in the first direction by the first contact sections which are flexible.